Detrusor-sphincter dyssynergia

Abstract

Neurological control of micturition is undertaken by central and peripheral nerve systems through complex neuronal interconnections that are mediated by the action of several neurotransmitters, finally controlling the function of detrusor muscle and external urethral sphincter. In normal circumstances, both muscles must have co-ordinated contractions in such a way that when the detrusor contracts, the external urethral sphincter relaxes. The loss of this co-ordinated action leads to the so-called syndrome of detrusor-sphincter dyssynergia. Without adequate treatment, more than 50% of men with this condition will develop severe complications. There are several neurological diseases that might lead to this condition where a common physiopathology consists of a distortion of the complex neural mechanism innervating the lower urinary tract. Because of this complexity, it is difficult to find a curative treatment providing a definitive solution for a majority of patients. Although most of the currently available therapies only provide partial or temporary solutions, some modalities offer a promising perspective.

Diagnosing detrusor sphincter dyssynergia in the neurological patient

“…Type 1 DSD, there is a progressive increase in EUS contraction activity that peaks at maximal detrusor contraction followed by sudden relaxation of the EUS as the detrusor pressure declines allowing urination [ 3,5,16 ] . 2.…”

“…Patch electrodes are often preferred for easier placement, patient tolerance and allow greater mobility [ 18 ] . EMG fi ndings in DSD have been classifi ed into three types by Blaivas [ 3,5,16 ] .…”

“…Up to 50% of patients with DSD develop serious urological complications [ 5,14 ] . Untreated DSD has been associated with reduced bladder compliance, elevated upper tract pressures, VUR, hydronephrosis and renal failure [ 3,5,14,15 ] . Complications of DSD occur less frequently in women and patients with MS, perhaps due to lower detrusor pressures [ 3,9,10 ] .…”

“…Neurological conditions more commonly resulting in DSD include: SCI, MS, spinal dysraphism and transverse myelitis [ 2,5 -12 ] . In the absence of neurological abnormality, impaired coordination of bladder contraction and sphincter relaxation is more appropriately referred to as dysfunctional voiding or pelvic fl oor hyperactivity [ 3,13 ] .…”

“…This interruption of the spinobulbospinal pathways is thought to result in failed inhibition of spinal guarding refl exes, erroneous excitation of Onuf ' s nucleus causing EUS contraction to occur during detrusor contraction, generating elevated detrusor pressures [ 1,3,5 ] . Up to 50% of patients with DSD develop serious urological complications [ 5,14 ] .…”